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Required: A moral vision for gene editing

Redesigning Life asks some interesting questions about CRISPR gene editing. What we need now are some answers

New model army: what will editing the genome do to human variety?

Mark Joste/Millenium Images,UK

By Matthew Cobb

THERE is a revolution going on in the life sciences, one that has already transformed scientific discovery and will soon change medicine. It could even see us altering the ecosystem in a precise, targeted way. This revolution has a name – CRISPR – and the key part of John Parrington’s Redesigning Life is a good summary of the gene-editing technique that lies behind the acronym.

Like any major technological change, CRISPR raises profound ethical questions. Through its ease of use and technical simplicity, this tool enables us to manipulate genes in almost any organism. Procedures that would have seemed impossible only five years ago are now widely available.

Parrington intends his book to be a “useful starting point” for our ethical discussions about these possibilities. But to come to a conclusion about whether we should be “redesigning life”, we not only need to understand the science; we also need to be shown the potential consequences of its application, for both good and ill. When dealing with this vital question, the book stumbles.

We are told, for instance, that human cloning raises major ethical issues, but are given not one hint of what these are, who might raise them, or how legitimate they might be. At last December’s international summit meeting in Washington DC on the ethics of using CRISPR on humans, it was agreed to maintain a moratorium on germ-line manipulations that would be transmitted to future generations. The reader deserves a description of this decision, and a brief exploration of why it is a line that should not be crossed.

Ethical considerations seem to be added as an afterthought, rather than being interwoven with the excited descriptions of the latest technical developments.

“Procedures that would have seemed impossible only five years ago are now widely available“

This is particularly clear in the coverage of “gene drives”. Scientists have developed a technique to get a mutant gene to copy itself onto both copies of a given chromosome in an animal or plant. This procedure has been made much simpler by the application of CRISPR. Gene drives enable a gene to spread rapidly through a population; there are plans to use them to combat mosquito-borne diseases by making the flies sterile or unsuitable as hosts for various viruses and parasites.

On the surface, this may seem like an excellent idea. The trouble is, a gene drive is effectively a biological bomb that, once released, will explode with potentially unknown consequences.

Parrington briefly states that there are ecological concerns, but does not address the obvious question of who should decide whether a particular gene drive should be released.

Communities affected by Zika virus or malaria should obviously have a say, but the ease with which vectors are transported around the world – a factor that led to Zika’s recent arrival in the Americas – shows that what is decided in one place could have an effect in another.

Many scientists involved in this research are extremely worried about the dangers. Some have suggested that we should prepare a “reset button” in case it all goes wrong – a second gene drive, returning the genome of the altered species to its original form. Although this might help to halt inadvertent change, it would not do anything to restore the ecosystem to its original state.

The issue of regulation is at the heart of the new genetic technology, and an international regulatory authority, like those that control potentially lethal activities such as atomic energy or civil aviation, could be set up. Even a brief mention of such a possibility, and the reasons why it might or might not be created, would have made Redesigning Life much more useful.